Today, amid debates over the COVID-19 pandemic and its relationship to wild animals and deforestation, his landmark essay suggests another potential iteration as the origin of the new SARS-COV2 coronavirus is sought. It has been widely hypothesized that the virus is zoonotic, originating in bats and passing through another animal, possibly a pangolin or a dog, before jumping to humans in a market in Wuhan, China. At CIFOR, our work on viruses and forests examines conditions that make such transmissions possible.